It was known that amidoximes were synthesized generally by reacting nitriles and hydroxylamines (Houben-Weyl Methoden der Organischen Chemie Band VIII Sauerstoff ver Bindungen III p. 692).
It was reported that 2,3-difluoro-6-trifluoromethylbenzamidoxime, which was included in the benzamidoximes represented by Formula (II), could be produced by reacting 2,3-difluoro-6-trifluoromethylbenzonitrile with hydroxylamine hydrochloride in the presence of sodium carbonate or the like (WO 96/19442).
However, in conventional technology, if there is a very small amount of metal ions, such as iron, in a solvent or if a brown-glass or SUS vessel is used as a reaction vessel, the yield of a target amidoxime compound is strikingly reduced, and benzamides represented by Formula (III) ##STR3##
are produced in a large amount as byproducts.